Shale oil is a natural hydrocarbon derived from shale containing bitumens or oil which can be separated therefrom. Shale is said to be clay which is on the way to becoming rock, and therefore a formation that is comparatively soft and easily broken up into flake-like pieces and readily mixed with water. There are vast reservoirs of oil bearing shales throughout the continents, akin to sandstones and the like, the rock formation thereof consisting of many varieties of sedimentary materials that split readily into plates or laminae which can then be pulverized or granulated. It is the shales and/or like oil bearing deposits with which this invention is primarily concerned.
Oil is known to be insoluble in water and remains fluid above determinable temperatures, and which can be distilled from shale to produce, for example, 30-50 gallons per ton. However, refining of oil shale by distillation methods using the application of heat and the like consumes excessive energy and has its environment pollution effect. In other words, normal "cracking" processes and the like are not economical or clean as applied to the recovery of useful hydrocarbons from oil bearing shales. However, shales are fine grained rock formed by the hardening of clay, which readily fragments into granular form for intimate exposure of the oils captured therein, it being a general object of this invention to emulsify shale oil exposed by granulation of the oil shale from which it is separated. With the present invention, the exposed shale oil is emulsified with water, providing the end product of this process to be used as such and/or separated by further refinement into fuels and plastics etc.
Pulverized or granulated oil shale is readily mixed with water to form a "slurry", by means of which the exposed shale oil and water are intimately admixed. Emulsification of the admixture in the presence of particulate shale is an object of this invention, and to this end sonic vibration is directed into the admixture of shale oil, water and particulate shale to induce the comingling of the fluids, thereby drawing the shale oil into contact with the water. In carrying out this invention, the granulated oil shale and subsequent admixture thereof with water is dynamic, a moving column thereof being subjected to sonic energy for the intimate emulsification and/or homogenization of the shale oil and water, the particulate shale remaining as separable matter.
The admixture of shale oil and water comingled with the particulate granules of shale is moved dynamically by conveyor means, in a continuous manner, it being an object of this invention to separate the emulsion of shale oil and water from the particulate oil shale from which it has been withdrawn. With the present invention, pneumatics is employed to blow the product emulsion from the particulate shale, the latter being retained by a screen so as to be discharged as "tailings" adapted to reestablish the mining sources thereof.
The fluidity of oil depends greatly upon its temperature, and to this end it is an object to maintain fluidity commensurate with comingling with water and emulsifying therewith, and further to facilitate flow of shale oil from the particulate matter, as well as to facilitate homogenization and the percolation of air (or other gas) therethrough to cause separation. In practice, the fluids both liquid and gas and particulate matter as well are tempered in order to ensure the liquidity of the shale oil as desired, and all as circumstances require.